Headlights Slightly Dim With Screen Heater On

[danzman1991]

Hi,

I noticed tonight, that when my screen heater is on, the headlights, lights on the dials and the clock etc go slightly dim when its on.. When I turn the screen heater on there is a little clicking noise coming from the fuse box (this happens when I beep the horn too)

Why is this?

Thanks,

Dan.

[jay1981]

The clicking from the fusebox is a just the relay switching, perfectly normal. As for the lights dimming could be an idea to check alternator output.

[mickyfree]

The clicking from the fusebox is a just the relay switching, perfectly normal. As for the lights dimming could be an idea to check alternator output.

Would that be the same for reving? For example I've pulled up and ready to parallel park and when I put the gear into reverse and start to move (a little acceleration) the headlights starts to flicker.

[danzman1991]

The clicking from the fusebox is a just the relay switching, perfectly normal. As for the lights dimming could be an idea to check alternator output.

How do I check this?

[CAR PARTS EXPRESS]

sounds like alternator on way out...get a multi meter check battery voltage when engine off then check when running...should be higher. post results on here

[Slugsy]

sounds like alternator on way out...get a multi meter check battery voltage when engine off then check when running...should be higher. post results on here

Does the "ford dash board trick" show the voltage. Thought it did...or is this not very accurate??

[CAR PARTS EXPRESS]

The dash would only show dtc's then you would have to look them up IF there was a voltage fault code present.... its simple with a multi meter

[artscot79]

The dash would only show dtc's then you would have to look them up IF there was a voltage fault code present.... its simple with a multi meter

the rear cre uses a high output thats why the lights dim the fog lightsd are a high out put as well in short if the battery is charged and the alternator is fine theres no problem i bet when you turn the switch off the lights go back to normal? the screen uses a higher voltage than most of the other electrics youll see the lights do it when you put elec windows uop and keep the button held for a second when its shut

[LEWDAN]

Hi,

I noticed tonight, that when my screen heater is on, the headlights, lights on the dials and the clock etc go slightly dim when its on.. When I turn the screen heater on there is a little clicking noise coming from the fuse box (this happens when I beep the horn too)

Why is this?

Thanks,

Dan.

Would think the alternator is giving this problem, had a fault on mine when the lights seemed to be pulsing bright then dim, was not long before battery indicator came on, knew then that the alternator had crashed :( get it checked out mate

LD

[artscot79]

any garag will do a free test for you ide be surprised if it is the alternator as it only does it wityh the heater switched on which as i said is a high draw circuit hence why it switches itself off after 15minutes simple way to check enter the diagnostic mode go to voltage and turn all the electrics on it shouldnt drop below 12.5v then rev the car slightly if the voltage increases the alternators doing its job also when the lights dim if you rev the car a bit the lights should brighten this will show the alternators working if it doesnt brighten the alternators goosed